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Abstract:

Systems and methods are disclosed for using multiple configuration groups
having corresponding configuration identity (CID) parameters to configure
a transmission channel and a reception channel for a user equipment
device in a cellular communication network. In one embodiment, a user
equipment device in a cellular communication network obtains CID values
for CID parameters for a number of configuration groups. Each of the
configuration groups includes one or more transmission channel or
reception channel parameters. For each of the configuration groups, the
user equipment device configures the parameters in the configuration
group based on the CID value obtained for the CID parameter for the
configuration group. In this manner, the transmission channel and the
reception channel for the user equipment device are configured based on
multiple CID values rather than a single physical layer cell identifier
for a cell in which the user equipment device is located.

Claims:

1. A method of operation of a user equipment device in a cellular
communication network, comprising: obtaining a plurality of configuration
identity values for configuration identity parameters for a corresponding
plurality of configuration groups for the user equipment device, where
each configuration group of the plurality of configuration groups has a
corresponding configuration identity parameter and includes a one or more
parameters for one of a transmission channel and a reception channel for
the user equipment device; and for each configuration group of the
plurality of configuration groups, configuring the one or more parameters
for the configuration group based on one of the plurality of
configuration identity values obtained for the corresponding
configuration identity parameter for the configuration group.

2. The method of claim 1 wherein the cellular communication network
comprises a macro node serving a cell in which the user equipment device
is located and a pico node that provides a data rate and capacity
extension for the cell within a corresponding pico region.

3. The method of claim 2 wherein for each configuration group of the
plurality of configuration groups, configuring the one or more parameters
for the configuration group comprises configuring the one or more
parameters based on the one of the plurality of configuration identity
values obtained for the corresponding configuration identity parameter
for the configuration group rather than a physical layer cell identifier.

4. The method of claim 2 wherein the plurality of configuration groups
comprise a transmission channel configuration group that includes one or
more transmission channel parameters and a reception channel
configuration group that includes one or more reception channel
parameters.

5. The method of claim 4 wherein the one or more transmission channel
parameters are one or more uplink parameters comprising at least one of a
group consisting of: an uplink frequency hopping parameter, an uplink
scrambling parameter, and an uplink user equipment device-specific
reference sequence parameter.

6. The method of claim 5 wherein the one or more reception channel
parameters are one or more downlink parameters comprising at least one of
a group consisting of: one or more downlink scrambling parameters, one or
more downlink frequency hopping parameters, a cell specific reference
sequence parameter, and a time-frequency mapping parameter for a cell
specific reference sequence.

7. The method of claim 2 wherein the plurality of configuration groups
comprise an uplink configuration group that includes one or more uplink
parameters, a cell-specific downlink configuration group that includes
one or more cell-specific downlink parameters, and a user equipment
device-specific downlink configuration group that includes one or more
user equipment device-specific downlink parameters.

9. The method of claim 2 wherein obtaining the plurality of configuration
identity values comprises: obtaining a physical layer cell identifier for
the cell; setting the plurality of configuration identity values to the
physical layer cell identifier as a default; receiving, for at least one
of the configuration identity parameters, an override configuration
identity value from the cellular communication network; and storing the
override configuration identity value as the configuration identity value
for the at least one of the configuration identity parameters.

10. The method of claim 2 wherein: obtaining the plurality of
configuration identity values comprises: storing a plurality of sets of
configuration identity values, each set of configuration identity values
comprising a different plurality of configuration identity values for the
configuration identity parameters of the plurality of configuration
groups for the user equipment device; and receiving an indicator that
identifies one of the plurality of sets of configuration identity values;
and for each configuration group of the plurality of configuration
groups, configuring the one or more parameters for the configuration
group comprises configuring the one or more parameters for the
configuration group based on the one of the plurality of sets of
configuration identity values identified by the indicator.

11. The method of claim 2 wherein: obtaining the plurality of
configuration identity values comprises: storing a plurality of sets of
configuration identity values, each set of configuration identity values
comprising a different plurality of configuration identity values for the
configuration identity parameters of the plurality of configuration
groups for the user equipment device; obtaining a location of the user
equipment device within the cell; and selecting one of the plurality of
sets of configuration identity values based on the location of the user
equipment device within the cell; and for each configuration group of the
plurality of configuration groups, configuring the one or more parameters
for the configuration group comprises configuring the one or more
parameters for the configuration group based on the one of the plurality
of sets of configuration identity values.

12. The method of claim 2 wherein the plurality of configuration groups
for the user equipment device are static.

13. The method of claim 2 wherein the plurality of configuration groups
for the user equipment device are dynamic.

14. The method of claim 2 further comprising receiving information that
maps parameters to configuration groups for at least a subset of the one
or more parameters for each of at least a subset of the plurality of
configuration groups.

15. The method of claim 2 further comprising: receiving information that
defines a relationship between one of the configuration identity
parameters and one of the one or more parameters in a corresponding one
of the plurality of configuration groups; and wherein, for the one of the
plurality of configuration groups, configuring the one or more parameters
included in the one of the plurality of configuration groups comprises
configuring the one of the one or more parameters based on one of the
plurality of configuration identity values obtained for the one of the
configuration identity parameters and the information that defines the
relationship between the one of the configuration identity parameters and
the one of the one or more parameters.

16. A user equipment device enabled to operate in a cellular
communication network, comprising: a transceiver subsystem adapted to
provide a transmission channel and a reception channel for the user
equipment device; and a processing subsystem associated with the
transceiver subsystem that is adapted to: obtain a plurality of
configuration identity values for configuration identity parameters for a
corresponding plurality of configuration groups for the user equipment
device, where each configuration group of the plurality of configuration
groups has a corresponding configuration identity parameter and includes
one or more parameters for one of the transmission channel and the
reception channel for the user equipment device; and for each
configuration group of the plurality of configuration groups, configuring
the one or more parameters for the configuration group based on one of
the plurality of configuration identity values obtained for the
corresponding configuration identity parameter for the configuration
group.

17. The user equipment device of claim 16 wherein for each configuration
group of the plurality of configuration groups, the processing subsystem
is further adapted to configure the one or more parameters for the
configuration group based on the one of the plurality of configuration
identity values obtained for the corresponding configuration identity
parameter for the configuration group rather than a physical layer cell
identifier.

18. The user equipment device of claim 16 wherein the plurality of
configuration groups comprise a transmission channel configuration group
that includes one or more transmission channel parameters and a reception
channel configuration group that includes one or more reception channel
parameters.

19. The user equipment device of claim 16 wherein the plurality of
configuration groups comprise an uplink configuration group that includes
one or more uplink parameters, a cell-specific downlink configuration
group that includes one or more cell-specific downlink parameters, and a
user equipment device-specific downlink configuration group that includes
one or more user equipment device-specific downlink parameters.

20. A method of operation of a network node in a cellular communication
network, comprising: determining a location of a user equipment device in
a cell served by a macro node; determining a plurality of configuration
identity values for configuration identity parameters for a corresponding
plurality of configuration groups for the user equipment device based on
the location of the user equipment device in the cell; and providing the
plurality of configuration identity values to the user equipment device.

21. The method of claim 20 wherein each configuration group of the
plurality of configuration groups for the user equipment device has a
corresponding configuration identity parameter and includes one or more
parameters for one of a transmission channel and a reception channel for
the user equipment device that are configured based on one of the
plurality of configuration identity values obtained for the corresponding
configuration identity parameter for the configuration group.

22. The method of claim 21 further comprising sending information to the
user equipment device that maps parameters to configuration groups for at
least a subset of the one or more parameters for at least a subset of the
plurality of configuration groups.

23. The method of claim 21 further comprising sending information to the
user equipment device that defines a relationship between one of the
configuration identity parameters and one of the one or more parameters
in a corresponding one of the plurality of configuration groups.

24. The method of claim 20 wherein providing the plurality of
configuration identity values to the user equipment device comprises
sending the plurality of configuration identity values to the user
equipment device.

25. The method of claim 20 wherein a plurality of sets of configuration
identity values are stored by the user equipment device, and providing
the plurality of configuration identity values to the user equipment
device comprises sending a predetermined indicator for one of the
plurality of sets of configuration identity values to the user equipment
device.

26. The method of claim 20 further comprising: storing a first
predetermined set of configuration identity values for a boundary region
at a boundary of the cell served by the macro node and a pico region
served by a pico node in the cellular communication network, a second
predetermined set of configuration identity values for the pico region,
and a third predetermined set of configuration identity values for a
macro region that includes at least a portion of the cell outside of the
pico region and the boundary region; wherein determining the plurality of
configuration identity values comprises setting the plurality of
configuration identity values for the user equipment device to one of the
first, second, and third predetermined sets of configuration identity
values based on the location of the user equipment device.

27. The method of claim 26 wherein: determining the location of the user
equipment device comprises determining that the user equipment device is
located in the boundary region; and determining the plurality of
configuration identity values comprises setting the plurality of
configuration identity values for the user equipment device to the first
predetermined set of configuration identity values for the boundary
region in response to determining that the location of the user equipment
device is in the boundary region.

28. The method of claim 26 wherein: determining the location of the user
equipment device comprises determining that the user equipment device is
located in the pico region; and determining the plurality of
configuration identity values comprises setting the plurality of
configuration identity values for the user equipment device to the second
predetermined set of configuration identity values for the pico region in
response to determining that the location of the user equipment device is
in the pico region.

29. The method of claim 26 wherein: determining the location of the user
equipment device comprises determining that the user equipment device is
located in the macro region; and determining the plurality of
configuration identity values comprises setting the plurality of
configuration identity values for the user equipment device to the third
predetermined set of configuration identity values for the macro region
in response to determining that the location of the user equipment device
is in the macro region.

30. A network node in a cellular communication network, comprising: a
transceiver subsystem; and a processing subsystem associated with the
transceiver subsystem and adapted to: determine a location of a user
equipment device in a cell served by a macro node; determine a plurality
of configuration identity values for configuration identity parameters
for a corresponding plurality of configuration groups for the user
equipment device based on the location of the user equipment device in
the cell; and provide the plurality of configuration identity values to
the user equipment device via the transceiver subsystem.

31. The network node of claim 30 wherein each configuration group of the
plurality of configuration groups for the user equipment device has a
corresponding configuration identity parameter and includes one or more
parameters for one of a transmission channel and a reception channel for
the user equipment device that are configured based on one of the
plurality of configuration identity values obtained for the corresponding
configuration identity parameter for the configuration group.

32. The network node of claim 31 wherein the processing subsystem is
further adapted to send, via the transceiver subsystem, information to
the user equipment device that maps parameters to configuration groups
for at least a subset of the one or more parameters for at least a subset
of the plurality of configuration groups.

33. The network node of claim 31 wherein the processing subsystem is
further adapted to send, via the transceiver subsystem, information to
the user equipment device that defines a relationship between one of the
configuration identity parameters and one of the one or more parameters
in a corresponding one of the plurality of configuration groups.

34. The network node of claim 30 wherein, in order to provide the
plurality of configuration identity values to the user equipment device,
the processing subsystem is further adapted to send the plurality of
configuration identity values to the user equipment device.

35. The network node of claim 30 wherein a plurality of sets of
configuration identity values are stored by the user equipment device
and, in order to provide the plurality of configuration identity values
to the user equipment device, the processing subsystem is further adapted
to send a predetermined indicator for one of the plurality of sets of
configuration identity values to the user equipment device.

36. The network node of claim 30 wherein: the network node stores a first
predetermined set of configuration identity values for a boundary region
at a boundary of the cell served by the macro node and a pico region
served by a pico node in the cellular communication network, a second
predetermined set of configuration identity values for the pico region,
and a third predetermined set of configuration identity values for a
macro region that includes at least a portion of the cell outside of the
pico region and the boundary region; and in order to determine the
plurality of configuration identity values, the processing subsystem is
further adapted to set the plurality of configuration identity values for
the user equipment device to one of the first, second, and third
predetermined sets of configuration identity values based on the location
of the user equipment device.

37. The network node of claim 36 wherein: the processing subsystem
determines that the user equipment device is located in the boundary
region; and in order to determine the plurality of configuration identity
values, the processing subsystem is further adapted to set the plurality
of configuration identity values for the user equipment device to the
first predetermined set of configuration identity values for the boundary
region in response to determining that the location of the user equipment
device is in the boundary region.

38. The network node of claim 36 wherein: the processing subsystem
determines that the user equipment device is located in the pico region;
and in order to determine the plurality of configuration identity values,
the processing subsystem is further adapted to set the plurality of
configuration identity values for the user equipment device to the second
predetermined set of configuration identity values for the pico region in
response to determining that the location of the user equipment device is
in the pico region.

39. The network node of claim 36 wherein: the processing subsystem
determines that the user equipment device is located in the macro region;
and in order to determine the plurality of configuration identity values,
the processing subsystem is further adapted to set the plurality of
configuration identity values for the user equipment device to the third
predetermined set of configuration identity values for the macro region
in response to determining that the location of the user equipment device
is in the macro region.

Description:

RELATED APPLICATIONS

[0001] This application claims the benefit of provisional patent
application serial number 61/483,972, filed May 9, 2011, the disclosure
of which is hereby incorporated herein by reference in its entirety.

[0003] The Long Term Evolution (LTE) standard defines multiple channel
types to organize transmissions between a base station and a mobile
terminal.

[0004] Logical channels are characterized by the type of information
transmitted, and transport channels are characterized by how the
information is transmitted.

[0005] The set of logical-channel types specified for LTE includes:

[0006] Broadcast Control Channel (BCCH): BCCH is used for transmission of
system information from the network to all mobile terminals in a cell.
This is information that is repeatedly broadcast by the network and which
needs to be acquired by mobile terminals in order for the mobile
terminals to be able to access and, in general, operate properly within
the network and within a specific cell. The system information includes,
among other things, information about downlink and uplink cell
bandwidths, uplink/downlink configuration in case of Time Division
Duplexing (TDD), detailed parameters related to random-access
transmission and uplink power control, etc.

[0007] Paging Control Channel (PCCH): PCCH is used for paging of mobile
terminals whose locations on a cell level are not known to the network.

[0008] Common Control Channel (CCCH): CCCH is used for transmission of
control information in conjunction with random access.

[0009] Dedicated Control Channel (DCCH): DCCH is used for transmission of
control information to/from a mobile terminal. This channel is used for
individual configuration of mobile terminals such as different handover
messages.

[0010] Multicast Control Channel (MCCH): MCCH is used for transmission of
control information required for reception of the MTCH (for MTCH, see
below).

[0011] Dedicated Traffic Channel (DTCH): DTCH is used for transmission of
user data to/from a mobile terminal. This is the logical-channel type
used for transmission of all uplink and non-Multimedia Broadcast over a
Single Frequency Network (MBSFN) downlink user data.

[0014] Broadcast Channel (BCH): BCH has a fixed transport format, provided
by the LTE specifications. It is used for transmission of parts of the
BCCH system information.

[0015] Paging Channel (PCH): PCH is used for transmission of paging
information from the PCCH logical channel.

[0016] Downlink Shared Channel (DL-SCH): DL-SCH is the main transport
channel used for transmission of downlink data in LTE. It supports key
LTE features such as dynamic rate adaptation and channel-dependent
scheduling in the time and frequency domains, hybrid Automatic Repeat
Request (ARQ) with soft combining, and spatial multiplexing. DL-SCH is
also used for transmission of the parts of the BCCH system information
not mapped to the BCH. There can be multiple DL-SCHs in a cell, one per
user equipment device (UE) scheduled in this Transmission Time Interval
(TTI), and, in some subframes, one DL-SCH carrying system information.

[0017] Multicast Channel (MCH): MCH is used to support MBMS.

[0018] Uplink Shared Channel (UL-SCH): UL-SCH is the uplink counterpart to
the DL-SCH, that is, the uplink transport channel used for transmission
of uplink data.

[0019] Random Access Channel (RACH): RACH is used for random access.

[0020] Logical channels are multiplexed and mapped to transport channels
as shown in FIG. 1 for the downlink and FIG. 2 for the uplink. The
information on a transport channel is then further processed by the
physical layer before transmission over the air interface to the
receiver.

[0021] The physical layer is responsible for scrambling, coding,
physical-layer hybrid-ARQ processing, modulation, multi-antenna
processing, and mapping of the signal to the appropriate physical
time-frequency resources. The physical layer also handles mapping of
transport channels to physical channels.

[0022] A physical channel corresponds to the set of time-frequency
resources used for transmission of a particular transport channel and
each transport channel is mapped to a corresponding physical channel. In
addition to the physical channels with a corresponding transport channel,
there are also physical channels without a corresponding transport
channel. These channels, known as L1/L2 control channels, are used for
Downlink Control Information (DCI), providing the mobile terminal with
the necessary information for proper reception and decoding of the
downlink data transmission, and Uplink Control Information (UCI) used for
providing the scheduler and the hybrid-ARQ protocol with information
about the situation in the mobile terminal.

[0023] The physical-channel types defined in LTE include the following:

[0024] Physical Downlink Shared Channel (PDSCH): PDSCH is the main
physical channel used for unicast transmission, but also for transmission
of paging information.

[0025] Physical Broadcast Channel (PBCH): PBCH carries part of the system
information required by the terminal in order to access the network.

[0027] Physical Downlink Control Channel (PDCCH): PDCCH is used for
downlink control information, mainly scheduling decisions, required for
reception of PDSCH and for scheduling grants enabling transmission on the
PUSCH (for PUSCH, see below).

[0028] Physical Hybrid-ARQ Indicator Channel (PHICH): PHICH carries the
hybrid-ARQ acknowledgement to indicate to the terminal whether a
transport block should be retransmitted or not.

[0029] Physical Control Format Indicator Channel (PCFICH): PCFICH is a
channel providing the terminals with information necessary to decode the
set of PDCCHs. There is only one PCFICH per component carrier.

[0030] Physical Uplink Shared Channel (PUSCH): PUSCH is the uplink
counterpart to the PDSCH. There is at most one PUSCH per uplink component
carrier per terminal.

[0031] Physical Uplink Control Channel (PUCCH): PUCCH is used by the
terminal to send hybrid-ARQ acknowledgements, indicating to the eNodeB
whether the downlink transport block(s) was successfully received or not,
to send channel-status reports aiding downlink channel-dependent
scheduling, and for requesting resources to transmit uplink data upon.
There is at most one PUCCH per terminal.

[0033] The mapping between transport channels and physical channels is
illustrated in FIG. 1 for the downlink and FIG. 2 for the uplink. Note
that some of the physical channels, more specifically the channels used
for downlink control information (PCFICH, PDCCH, PHICH) and uplink
control information (PUCCH), do not have a corresponding transport
channel.

[0034] The different steps of the DL-SCH physical layer processing are
outlined in FIG. 3. To randomize the interference between cells, LTE uses
(cell-specific) scrambling of the coded transport channel data prior to
mapping to the time-frequency resources. The purpose of scrambling (or,
in general, randomization) is to make a signal to appear as random
"noise" to a receiver not applying the correct descrambling sequence.
Randomizing the transmitted data is beneficial as it allows spatial reuse
of transmission resources. Although the resources are separated in the
spatial domain, the isolation will often not be perfect (commonly
referred to as the transmissions not being perfectly orthogonal). Thus,
transmissions in one area may interfere with transmissions in another
area. To avoid the receiver demodulating the wrong transmission, it is
beneficial to ensure that any interference appears as random noise at the
receiver. This is a well-known principle and has been used in several
cellular systems supporting frequency reuse between cells, e.g., Wideband
Code Division Multiple Access (WCDMA)/High Speed Packet Access (HSPA),
LTE, and Code Division Multiple Access 2000 (CDMA2000). Sometimes the
term quasi-orthogonal transmission is used to refer to the situation when
multiple transmissions are not perfectly isolated (in time, frequency,
code, or spatial domains) but randomization has been used to reduce the
impact from one transmission to another.

[0035] The remaining downlink transport channels are based on the same
general physical-layer processing as the DL-SCH, although with some
restrictions in the set of features used. The UL-SCH in the uplink also
follows similar physical-layer processing although there are some, for
this disclosure irrelevant, differences such as the used of Discrete
Fourier Transform (DFT) precoding for the UL-SCH.

[0036] Orthogonal Frequency Division Multiplexing (OFDM) is the basic
transmission scheme for both the downlink and uplink transmission
directions in LTE although, for the uplink, specific means are taken to
ensure efficient power-amplifier operation. In the time domain, LTE
transmission is organized into (radio) frames of length 10 milliseconds
(ms), each of which is divided into ten equally sized subframes of length
1 ms as illustrated in FIG. 4. Each subframe consists of two equally
sized slots of length Tslot=0.5 ms with each slot consisting of a
number of OFDM symbols including cyclic prefix.

[0037] A resource element, consisting of one subcarrier during one OFDM
symbol, is the smallest physical resource in LTE. Furthermore, as
illustrated in FIG. 5, subcarriers are grouped into resource blocks,
where each resource block consists of 12 consecutive subcarriers in the
frequency domain and one 0.5 ms slot in the time domain. Each resource
block thus consists of 7×12=84 resource elements in case of normal
cyclic prefix and 6×12=72 resource elements in case of extended
cyclic prefix. Although resource blocks are defined over one slot, the
basic time domain unit for dynamic scheduling in LTE is one subframe,
consisting of two consecutive slots. The minimum scheduling unit
consisting of two time-consecutive resource blocks within one subframe
(one resource block per slot) can be referred to as a resource block
pair. The resource block definition above applies to both the downlink
and uplink transmission directions.

[0038] Downlink reference signals are predefined signals occupying
specific resource elements within the downlink time-frequency grid. The
LTE specification includes several types of downlink reference signals
which are transmitted in different ways and used for different purposes
by the receiving terminal.

[0039] Cell-Specific Reference Signals (CRSs) are transmitted in every
downlink subframe and in every resource block in the frequency domain,
thus covering the entire cell bandwidth. The CRSs can be used by the
terminal for channel estimation for coherent demodulation.

[0040] Demodulation Reference Signals (DM-RSs), also sometimes referred to
as UE-specific reference signals, are specifically intended to be used by
terminals for channel estimation for PDSCH when the CRSs cannot be used.
The label "UE-specific" relates to the fact that each demodulation
reference signal is intended for channel estimation by a single terminal.
That specific reference signal is then only transmitted within the
resource blocks assigned for PDSCH transmission to that terminal.

[0041] CSI Reference Signals (CSI-RSs) are specifically intended to be
used by terminals to acquire Channel-State Information (CSI) in case when

[0042] DM-RSs are used for channel estimation. CSI-RSs have a
significantly lower time/frequency density, and thus implies less
overhead, compared to the CRSs. A terminal can be provided with
information about multiple CSI-RSs, one to measure upon and one or
several that the terminal shall treat as "unused" resource elements
(CSI-RS muting).

[0043] MBSFN reference signals are intended to be used for channel
estimation for coherent demodulation in case of MCH transmission using
MBSFN.

[0044] Positioning Reference Signals (PRSs) were introduced in LTE release
9 to enhance LTE positioning functionality, and more specifically to
support the use of terminal measurements on multiple LTE cells to
estimate the geographical position of the terminal. The positioning
reference symbols of a certain cell can be configured to correspond to
empty resource elements in neighboring cells, thus enabling
high-Signal-to-Interference (SIR) conditions when receiving neighboring
cell positioning reference signals.

[0045] There are two types of reference signals defined for the LTE
uplink:

[0046] Uplink DM-RSs are intended to be used by the base station for
channel estimation for coherent demodulation of the uplink physical
channels (PUSCH and PUCCH). DM-RSs are thus only transmitted together
with PUSCH or PUCCH and are then transmitted with the same bandwidth as
the corresponding physical channel.

[0047] Uplink Sounding Reference Signals (SRSs) are intended to be used by
the base station for channel-state estimation to support uplink
channel-dependent scheduling and link adaptation. The SRSs can also be
used in cases when uplink transmission is needed although there is no
data to transmit. Sounding reference signals can either be transmitted
periodically as configured by higher layers or as "one shot" upon request
from the network.

[0048] Reference signals of different types, both in uplink and downlink,
are typically separated in the time and/or frequency domain. For example,
the downlink CRSs and DM-RSs from the same cell occupy different resource
elements. These reference signals are therefore said to be orthogonal as
no interference will occur between the two. However, between reference
signals of the same type but belonging to different cells or different
terminals, orthogonality can in general not be provided as this would
result in excessive resource consumption. Therefore, the reference signal
sequences and the processing in general is such that two reference
signals use the same time-frequency resources but with different
(pseudo-random) sequences to reduce impact from one reference signal to
another. In essence, this idea of quasi-orthogonality is the same as
scrambling for the data transmission.

[0049] Cell search is the process in LTE where the terminal acquires
frequency and time synchronization to a cell and acquires the
physical-layer cell identity (ID) of the cell (there are in total
3×168=504 possible identities). To assist the cell search, two
special signals are transmitted on each downlink component carrier, the
Primary Synchronization Signal (PSS) and the Secondary Synchronization
Signal (SSS). Although having the same detailed structure, the
time-domain positions of the synchronization signals within the frame
differ somewhat depending on if the cell is operating in Frequency
Division Duplexing (FDD) or TDD mode. Time and frequency synchronization
is required at the receiver (i.e., the UE) in order to properly receive
and process any information transmitted by the transmitter (i.e., the
base station).

[0050] The physical-layer cell identity of the cell in which the terminal
has located is obtained by the terminal and is used for multiple purposes
in LTE including:

[0051] for uplink transmissions: [0052] to determine the scrambling
sequence used for the PUSCH uplink channel and the pseudo-random sequence
used for the PUCCH uplink channel; [0053] to determine the frequency
hopping pattern for uplink transmission on PUSCH (if hopping is enabled);
[0054] to determine the sequence and, if enabled, sequence hopping
pattern for uplink DM-RS; and [0055] to determine the sequence and, if
enabled, sequence hopping pattern for uplink SRS;

[0056] for downlink transmissions: [0057] to determine the scrambling
sequence for downlink unicast data transmission on PDSCH; [0058] to
determine the scrambling sequence for downlink broadcast of system
information (PBCH and Broadcast Channel (BCH) mapped to PDSCH) and paging
(PCH mapped to PDSCH); and [0059] to determine the scrambling and
time-frequency mapping of the PCFICH, PHICH, and PDCCH, used for
transmission of downlink control information; and

[0060] for downlink reference signals: [0061] to determine the sequence
and the frequency location used for the CRSs; [0062] to determine the
sequence and, in some cases (antenna port 5) the frequency-domain
location used for the UE-specific DM-RSs; [0063] to determine the
sequence and the frequency location used for the PRSs; and [0064] to
determine the sequence used for the CSI-RSs. Thus, as can be seen from
the extensive list above, the physical-layer identity of the cell to
which the terminal is connected influences many functions as seen in FIG.
6. In particular,

[0065] uplink transmission,

[0066] downlink unicast reception, and

[0067] downlink broadcast reception

all use functions with parameters derived from the same physical-layer
cell ID.

[0068] The use of a so called heterogeneous deployment or heterogeneous
cellular communication network is considered to be an interesting
deployment strategy for cellular communication networks. As illustrated
in FIG. 7, a heterogeneous deployment 10 includes a macro node 12 (i.e.,
a macro base station) and a pico node 14 (i.e., a pico base station) with
different transmit powers and with overlapping coverage areas. Notably, a
heterogeneous cellular communication network typically includes numerous
macro nodes 12 and numerous pico nodes 14. In such a deployment, the pico
nodes 14 are typically assumed to offer high data rates (megabits per
second (Mbit/s)), as well as provide high capacity (users per square
meters (users/m2) or Mbit/s/m2), in the local areas where this
is needed/desired, while the macro nodes 12 are assumed to provide
full-area coverage. In practice, the macro nodes 12 may correspond to
currently deployed macro cells while the pico nodes 14 are later deployed
nodes, extending the capacity and/or achievable data rates within a macro
cell 16 served by the macro node 12 where needed. In a typical case,
there may be multiple pico nodes 14 within the macro cell 16.

[0069] The pico node 14 of the heterogeneous deployment 10 typically
corresponds to a cell of its own, i.e., a pico cell 18, as illustrated in
FIG. 8 where the indices "p" and "m" indicate common signals/channels for
the pico and macro cells 16 and 18, respectively. This means that, in
addition to downlink and uplink data transmission/reception, the pico
node 14 also transmits the full set of common signals/channels associated
with a cell. In the LTE context this includes:

[0070] The PSSs and SSSs corresponding to the physical-layer cell ID of
the pico cell 18,

[0071] The CRSs, also corresponding to the physical-layer cell ID of the
pico cell 18. The CRS can, for example, be used for downlink channel
estimation to enable coherent demodulation of downlink transmissions.

[0072] The BCH with corresponding pico cell system information for the
pico cell 18. As the pico node 14 transmits the common signals/channels,
the corresponding pico cell 18 can be detected and selected (connected
to) by a UE.

[0073] If the pico node 14 corresponds to a cell of its own, so-called
L1/L2 control signaling on the PDCCH physical channel are also
transmitted from the pico node 14 to connected UEs in addition to
downlink data transmission on the PDSCH physical channel. For example,
the L1/L2 control signaling provides downlink and uplink scheduling
information and hybrid-ARQ related information to UEs within the cell.

[0074] In a heterogeneous deployment with a pico node corresponding to a
cell of its own (FIG. 8), there is an inherent downlink/uplink imbalance
due to the different transmit power of the macro and pico nodes/cells.
This imbalance is illustrated in FIG. 9. The UE may connect to the cell
(macro or pico) to which the path loss is the smallest. At least from an
uplink data rate point-of-view, this is preferred as, for a given
available UE transmit power, a smaller path loss leads to higher received
power and thus to the possibility for higher data rates. However, due to
the fact that common signals/channels as well as L1/L2 control channels
are transmitted with higher power from the macro cell 16, compared to the
pico cell 18, the UE connected to the pico cell 18 may experience very
high interference from the transmission of these signals/channels in the
macro cell 16. Although there are means to at least partly mitigate this
interference, this requires special UE functionality not necessarily
implemented in all UEs.

[0075] Alternatively, the UE may connect to the cell (macro or pico) from
which the common channels (in practice the cell-specific reference
signals) are received with the highest power. This is equivalent to say
that the UE connects to the cell with the lowest path loss, weighted by
the cell transmit power. However, due to the higher transmit power of the
macro cell 16, a UE may then connect to the overlaid macro cell 16 even
if the path loss to the pico cell 18 is smaller, leading to at least
lower uplink data rates and potentially also a reduced downlink
efficiency on a system level (although the downlink signals are received
with stronger power from the macro cell 16, this is achieved at the
expense of causing more downlink interference to other UEs).

SUMMARY

[0076] The present disclosure relates to using multiple configuration
groups having corresponding Configuration Identity (CID) parameters to
configure a transmission channel or reception channel for a user
equipment device in a cellular communication network. The cellular
communication network is, in one embodiment, a heterogeneous cellular
network. In one embodiment, a user equipment device in a cellular
communication network obtains CID values for CID parameters for a number
of configuration groups. Each of the configuration groups includes one or
more, but preferably multiple, transmission or reception channel
parameters. The transmission or reception channel parameters may be, for
example, uplink or downlink parameters. For each of the configuration
groups, the user equipment device configures the parameters in the
configuration group based on the CID value obtained for the CID parameter
for the configuration group. In this manner, the transmission and/or
reception channel for the user equipment device are configured based on
multiple CID values rather than a single physical layer cell identifier
for a cell in which the user equipment device is located.

[0077] In one embodiment, the cellular network is a heterogeneous cellular
network, and an uplink and the downlink of the user equipment device are
decoupled such that uplink transmissions from the user equipment device
are received by one or more antenna points independently from which
antenna point is used for downlink transmission to the user equipment
device. In this embodiment, the one or more configuration groups include
one or more downlink configuration groups and an uplink configuration
group. Each of the one or more downlink configuration groups and the
uplink configuration group has a number of parameters that are mapped to
that configuration group. The user equipment device obtains CID values
for the CID parameters of the downlink and uplink configuration groups.
For each of the downlink and uplink configuration groups, the user
equipment device configures the parameters mapped to the configuration
group based on the CID value obtained for the CID parameter for the
configuration group. By using the configuration groups rather than
independently configuring each individual parameter, the decoupled uplink
and downlink for the user equipment device are independently configured
while maintaining a low signaling overhead for configuration messages.

[0078] Those skilled in the art will appreciate the scope of the present
disclosure and realize additional aspects thereof after reading the
following detailed description of the preferred embodiments in
association with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

[0079] The accompanying drawing figures incorporated in and forming a part
of this specification illustrate several aspects of the disclosure, and
together with the description serve to explain the principles of the
disclosure.

[0080] FIG. 1 illustrates mapping of local channels to transport channels
for a downlink in Long Term Evolution (LTE) wireless communication
networks;

[0081]FIG. 2 illustrates mapping of local channels to transport channels
for an uplink in LTE wireless communication networks;

[0089]FIG. 10 illustrates a heterogeneous cellular communication network
according to one embodiment of the present disclosure;

[0090] FIG. 11 illustrates two exemplary configuration groups for a user
equipment device according to one embodiment of the present disclosure;

[0091]FIG. 12 illustrates the operation of a user equipment device
according to one embodiment of the present disclosure;

[0092] FIG. 13 illustrates the operation of the heterogeneous cellular
communication network of FIG. 10 to implement the process of FIG. 12
according to one embodiment of the present disclosure;

[0093]FIG. 14 illustrates the operation of the heterogeneous cellular
communication network of FIG. 10 to implement the process of FIG. 12
according to another embodiment of the present disclosure;

[0094]FIG. 15 illustrates the operation of the heterogeneous cellular
communication network of FIG. 10 to implement the process of FIG. 12
according to another embodiment of the present disclosure;

[0095]FIG. 16 illustrates one example of configuration groups and a
change in Configuration Identity (CID) values for CID parameters of the
configuration groups according to one embodiment of the present
disclosure;

[0096]FIG. 17 is a block diagram of a macro node according to one
embodiment of the present disclosure;

[0097]FIG. 18 is a block diagram of a pico node according to one
embodiment of the present disclosure; and

[0098]FIG. 19 is a block diagram of a user equipment device (UE)
according to one embodiment of the present disclosure.

DETAILED DESCRIPTION

[0099] The embodiments set forth below represent the necessary information
to enable those skilled in the art to practice the embodiments and
illustrate the best mode of practicing the embodiments. Upon reading the
following description in light of the accompanying drawing figures, those
skilled in the art will understand the concepts of the disclosure and
will recognize applications of these concepts not particularly addressed
herein. It should be understood that these concepts and applications fall
within the scope of the disclosure and the accompanying claims.

[0100]FIG. 10 illustrates a heterogeneous cellular communication network
20 in which user equipment devices (UEs), or mobile terminals, use
multiple configuration groups to configure parameters for uplink and
downlink according to one embodiment of the present disclosure. As
illustrated, the heterogeneous cellular communication network 20 includes
a macro node 22 and a pico node 24 that operate to serve a UE 26 located
within a cell 28 served by the macro node 22. The pico node 24 serves a
pico region 30 that, in this example, is within the cell 28. However, the
pico region 30 may otherwise overlap the cell 28. The pico region 30 is
not a pico cell. Rather, the pico region 30 is a region in which the pico
node 24 provides a beam extension for the overlaid cell 28 (i.e.,
provides a data rate and capacity extension of the overlaid cell 28).
Specifically, for Long Term Evolution (LTE), the pico node 24 transmits
the Physical Downlink Shared Channel (PDSCH), but the macro node 22
transmits the Cell-Specific Reference Signal (CRS), Primary
Synchronization Signal (PSS) and Secondary Synchronization Signal (SSS),
as well as channels such as Physical Downlink Control Channel (PDCCH) and
Physical Broadcast Channel (PBCH) relying on CRS for reception. To allow
for demodulation and detection of the PDSCH despite the fact that no CRS
is transmitted from the pico node 24, a Demodulation Reference Signal
(DM-RS) is transmitted from the pico node 24 together with the PDSCH. The
UE-specific reference signals can then be used by the UE 26 for PDSCH
demodulation/detection. Note that while FIG. 10 illustrates only one
macro node 22 and one pico node 24, the heterogeneous cellular
communication network 20 may include numerous macro nodes 22 and numerous
pico nodes 24. Further, multiple pico nodes 24 may be within the same
cell 28. Also, while only one UE 26 is illustrated for clarity and ease
of discussion, the cell 28 may serve numerous UEs 26.

[0101] In the heterogeneous cellular communication network 20, the problem
of excessive common/control-channel interference to UEs located in the
area served by the pico node 24 from the transmissions from the macro
node 22 is not present as the common channels and L1/L2 control channels
can be, in this case, transmitted from the macro node 22 even though
PDSCH is transmitted from the pico node 24. Notably, this does not rely
on any new functionality in the UEs but can allow existing UEs to exploit
the full gains of the pico node 24.

[0102] In one embodiment, the pico node 24 is implemented as a Remote
Radio Unit (RRU) connected to a central processing node also handling the
macro node 22. With this deployment approach, uplink transmissions from
the UE 26 can be received in any antenna point (i.e., any macro node 22
or pico node 24) or set of antenna points, independently from which
antenna point was used for transmission to the UE 26. In essence, an
uplink and downlink of the UE 26 have been decoupled. This provides
several advantages. For example, downlink transmissions to the UE 26 can
use the antenna point with the strongest received power, while uplink
transmissions from the UE 26 can be received in the antenna point with
the lowest path loss. Notably, the antenna point with the lowest path
loss may not be the same as the antenna point from which the downlink is
the strongest due to the difference in transmission power between antenna
points. For instance, in FIG. 10, there is a boundary region 32 at the
boundary of the cell 28 and the pico region 30 in which the uplink having
the lowest path loss is the uplink to the pico node 24 while the
strongest downlink is received from the macro node 22. The decoupled
uplink and downlink deployment strategy can of course be generalized
further such that a certain geographical area is covered by a plurality
of antenna points, all connected to the same processing node. Algorithms
in the centralized processing node can then, in a manner transparent to
the UE 26, determine which antenna points to use for downlink
transmission and uplink reception towards the UE 26.

[0103] In the heterogeneous cellular communication network 20 of FIG. 10,
it is desirable to couple the transmission structure (e.g., scrambling,
Reference Signal (RS) location, etc.) to the antenna point used for
communications in a particular downlink/uplink direction. If the uplink
of the UE 26 is received by a different antenna point than the antenna
point(s) used for downlink transmission to the UE 26, it is beneficial to
independently set the transmission structure for the two directions. This
is not possible in the current version of LTE (Rel-10) as both the uplink
and downlink transmission structures are derived from the same
physical-layer cell identity (ID). Furthermore, a relatively costly
handover procedure to another cell, requiring quite extensive Radio
Resource Control (RRC) signaling and causing corresponding delays, is
required if another transmission structure is desirable. One way to
address these problems is to provide for individual configuration of each
of the transmission parameters (e.g., scrambling sequences, reference
signal structure, etc). However, such individual configuration of each of
the transmission parameters would result in excessive overhead, which is
especially unattractive if handovers between cells are frequent.

[0104] The present disclosure relates to using multiple configuration
groups having corresponding Configuration Identity (CID) parameters to
configure an uplink and a downlink for a UE in a heterogeneous cellular
communication network, such as the heterogeneous cellular communication
network 20 of FIG. 10. Using the UE 26 as an example, in general, the
parameters for the uplink and the downlink for the UE 26 are divided into
multiple configuration groups such that each configuration group includes
one or more, and preferably multiple, uplink or downlink parameters. Each
configuration group has a separate CID parameter. In one embodiment, the
UE 26 obtains CID values for CID parameters for the configuration groups.
For each of the configuration groups, the UE 26 configures the parameters
in the configuration group based on the CID value obtained for the CID
parameter for the configuration group. In this manner, the uplink and the
downlink for the UE 26 are configured based on multiple CID values rather
than a single physical layer cell ID for a cell in which the UE 26 is
located. As such, transmission structures for the uplink and downlink are
independently configurable. This is particularly beneficial for a
heterogeneous cellular communication network such as that of FIG. 10
where the uplink and downlink for the UE 26 are decoupled.

[0105] It should be noted that while the discussion herein focuses
primarily on configuration groups to configure uplink and/or downlink
parameters for communication between UEs, such as the UE 26, and macro
node 22 and the pico node 24 in the heterogeneous cellular communication
network 20, the present disclosure is not limited thereto. The concepts
described herein can be used to provide configuration groups to configure
other types of transmission and/or reception link or channel parameters
for a UE in a cellular communication network. For example, the concepts
described herein may be used to provide configuration groups to configure
transmission and/or reception link parameters between a UE and another UE
for device-to-device communication.

[0106] FIG. 11 illustrates two exemplary configuration groups for the UE
26 according to one embodiment of the present disclosure. In this
exemplary embodiment, the configuration groups include a downlink
configuration group 34 and an uplink configuration group 36. The downlink
configuration group 34 has a corresponding downlink CID parameter and
includes a number of downlink parameters. The downlink parameters mapped
to the downlink configuration group 34 may be predefined (e.g., by a
specification) or received by the UE 26 from the heterogeneous cellular
communication network 20 (e.g., received from the macro node 22). For
example, a mapping of the downlink parameters to the downlink
configuration group 34 may be received via signaling such as, for
instance, RRC signaling. Further, the signaling of the mapping of the
downlink parameters to the downlink configuration group 34 may be UE
specific signaling or broadcast signaling received by multiple UEs in the
cell 28 including the UE 26.

[0107] In this example, the downlink parameters include a number of
downlink scrambling parameters, namely, a PDSCH scrambling parameter and
a Physical Control Format Indicator Channel (PCFICH)/Physical Hybrid
Automatic Repeat Request (ARQ) Indicator Channel (PHICH)/PDCCH scrambling
parameter; a time-frequency mapping parameter, namely, a
PCFICH/PHICH/PDCCH time-frequency mapping parameter and a CRS
time-frequency mapping parameter; and a cell-specific reference sequence,
namely, a CRS sequence parameter. As will be appreciated by one of
ordinary skill in the art, the downlink parameters may include additional
downlink parameters.

[0108] As discussed below, the downlink parameters are configured by the
UE 26 based on a CID value obtained for the downlink CID parameter using
known relationships between the downlink CID parameter and the downlink
parameters. In other words, values for the downlink parameters are
derived from the CID value obtained for the downlink CID parameter. The
CID value obtained for the downlink CID parameter may be received from
the heterogeneous cellular communication network 20 (e.g., received from
the macro node 22) via signaling or derived from a physical-layer cell ID
for the cell 28. For example, the CID value for the downlink CID
parameter may be signaled to the UE 26 via RRC signaling. Further, the
signaling of the CID value for the downlink CID parameter to the UE 26
may be UE specific signaling or signaling broadcast to multiple UEs
including the UE 26. As another example, the CID value for the downlink
CID parameter may be set to the physical-layer cell ID of the cell 28 as
a default and then overwritten via signaling from the heterogeneous
cellular communication network 20 (e.g., from the macro node 22) as
needed. The relationships between the downlink CID parameter and the
downlink parameters in the downlink configuration group may be predefined
(e.g., by a specification) or signaled to the UE 26 from the
heterogeneous cellular communication network 20 (e.g., received via
signaling from the macro node 22). Again, the signaling may be RRC
signaling. Further, the signaling may be UE specific or broadcast
signaling. The relationships may be represented as tables, formulas, or
the like.

[0109] The uplink configuration group 36 has a corresponding uplink CID
parameter and includes a number of uplink parameters. The uplink
parameters mapped to the uplink configuration group 36 may be predefined
(e.g., by a specification) or received by the UE 26 from the
heterogeneous cellular communication network 20 (e.g., received from the
macro node 22). For example, the mapping of the uplink parameters to the
uplink configuration group 36 may be received via signaling such as, for
instance, RRC signaling. Further, the signaling of the mapping of the
uplink parameters to the uplink configuration group 36 may be UE specific
signaling or broadcast signaling received by multiple UEs in the cell 28
including the UE 26.

[0110] In this example, the uplink parameters include an uplink frequency
hopping parameter, namely, a Physical Uplink Shared Channel (PUSCH)
frequency hopping parameter; an uplink scrambling parameter, namely, a
PUSCH scrambling parameter; and a UE-specific reference sequence, namely,
an uplink DM-RS sequence parameter. As will be appreciated by one of
ordinary skill in the art, the uplink parameters may include additional
uplink parameters.

[0111] As discussed below, the uplink parameters are configured by the UE
26 based on a CID value obtained for the uplink CID parameter using known
relationships between the uplink CID parameter and the uplink parameters.
In other words, values for the uplink parameters are derived from the CID
value obtained for the uplink CID parameter. The CID value obtained for
the uplink CID parameter may be received from the heterogeneous cellular
communication network 20 (e.g., received from the macro node 22) via
signaling or derived from a physical-layer cell ID for the cell 28. For
example, the CID value for the uplink CID parameter may be signaled to
the UE 26 via RRC signaling. Further, the signaling of the CID value for
the uplink CID parameter to the UE 26 may be UE specific signaling or
signaling broadcast to multiple UEs including the UE 26. As another
example, the CID value for the uplink CID parameter may be set to the
physical-layer cell ID of the cell 28 as a default and then overwritten
via signaling from the heterogeneous cellular communication network 20
(e.g., from the macro node 22) as needed. The relationships between the
uplink CID parameter and the uplink parameters in the uplink
configuration group may be predefined (e.g., by a specification) or
signaled to the UE 26 from the heterogeneous cellular communication
network 20 (e.g., received via signaling from the macro node 22). Again,
the signaling may be RRC signaling. Further, the signaling may be UE
specific or broadcast signaling. The relationships may be represented as
tables, formulas, or the like.

[0112] Using the heterogeneous cellular communication network 20 of FIG.
10 as an example, in one embodiment, if the UE 26 is located in the pico
region 30 as illustrated, the CID value obtained for the downlink CID
parameter and the CID value obtained for the uplink CID parameter are
both CID values (or a single CID value) associated with the pico node 24.
Conversely, if the UE 26 is located in the boundary region 32 at the
boundary between the cell 28 and the pico region 30, the CID value
obtained for the downlink CID parameter is a CID value associated with
the macro node 22, and the CID value obtained for the uplink CID
parameter is a CID value associated with the pico node 24. Still further,
if the UE 26 is located in the cell 28 outside of the pico region 30 and
the boundary region 32, the CID value obtained for the downlink CID
parameter and the CID value obtained for the uplink CID parameter are
both CID values (or a single CID value) associated with the macro node
22.

[0113] Note that the downlink and uplink configuration groups 34 and 36
are exemplary. The downlink and uplink parameters mapped to the downlink
and uplink configuration groups 34 and 36 may vary depending on the
particular implementation or network type of the heterogeneous cellular
communication network 20. Further, the configuration groups are not
limited to the uplink and downlink configuration groups 34 and 36.
Additional or alternative configuration groups may be defined. For
example, in another exemplary embodiment, the downlink parameters may be
divided into two separate configuration groups, namely, a cell-specific
configuration group and a UE-specific configuration group. The
cell-specific configuration group includes downlink parameters for
PSS/SSS and all functionality that makes use of CRS including the CRS
based PDCCH and PDSCH. The UE-specific configuration group includes
parameters for DM-RS, DM-RS based PDSCH and Channel-State Information
(CSI) Reference Signal (CSI-RS). The CID value for CID parameters for the
cell-specific configuration group may be the physical-layer cell ID of
the cell 28. A separate CID value is obtained for the CID parameter for
the UE-specific configuration group.

[0114] Splitting the downlink parameters into two groups as described in
the example above can also provide benefits in terms of network power
consumption. Broadcast of system information uses CRS-based reception of
PBCH, PDCCH, and PDSCH and is thus associated to the cell-specific
downlink configuration group while unicast data to a specific terminal
typically uses DM-RS-based reception of the PDSCH and are hence
associated with the UE-specific downlink configuration group. This allows
system information to be broadcast across multiple sites using Multimedia
Broadcast over a Single Frequency Network (MBSFN) transmission assuming
the same physical-layer cell ID is used in all of these sites with the
associated reference signal structures, etc. In addition, this allows
unicast information related to a certain UE to be delivered by a single
site only. Sites not used for unicast transmission to any UE at a
specific point in time may be turned off, which allows for a reduction in
network power consumption without having to reassign the UE to another
cell using a handover mechanism.

[0115] By using configuration groups such as those of FIG. 11, a
significant reduction in signaling compared to individual configuration
of each parameter is possible. Instead of reconfiguring each parameter in
a configuration group individually, a single CID value is signaled to or
otherwise obtained by the UE 26. Thus, in essence, for LTE, the present
disclosure replaces the physical-layer cell ID as it is related to
configuration of uplink and downlink parameters with multiple CID values,
which enables independent configuration of the parameters in the
different configuration groups. This can be seen as having different
"cells" for different types of transmissions.

[0116]FIG. 12 illustrates the operation of the UE 26 according to one
embodiment of the present disclosure. Optionally, in some embodiments,
the UE 26 obtains a mapping of parameters to a number of configuration
groups (step 100). The mapping may be received from the heterogeneous
cellular communication network 20 via signaling from the heterogeneous
cellular communication network 20 (e.g., from the macro node 22). Note
that the UE 26 may initially store a default mapping of parameters to
configuration groups. The default mapping may then be overridden as
needed via signaling from the heterogeneous cellular communication
network 20. The signaling may change the number of configuration groups
and/or the parameters mapped to the configuration groups. Rather than
obtaining the mapping of the parameters to the configuration groups, the
mapping of the parameters to the configuration groups may alternatively
be stored by the UE 26 or hard-coded into hardware and/or software of the
UE 26. For instance, the configuration groups and the parameters mapped,
or assigned, to the configuration group may be statically defined by a
specification (e.g., the LTE specification) and therefore stored by or
hard-coded in the UE 26.

[0117] In addition, optionally in some embodiments, the UE 26 obtains
relationships between the parameters in the configuration groups and the
CID parameters of the configuration groups (step 102). For each
parameter, the relationship between the parameter and the CID parameter
of the corresponding configuration group may be defined by, for example,
a table, mathematical formula, or the like. The relationships may be
received from the heterogeneous cellular communication network 20 via
signaling from cellular communication network 20 (e.g., from the macro
node 22). Note that the UE 26 may initially store default relationships.
The default relationships may then be overridden as needed via signaling
from the heterogeneous cellular communication network 20. Rather than
obtaining the relationships between the parameters and the CID parameters
of the corresponding configuration groups, the relationships may
alternatively be stored by the UE 26 or hard-coded into hardware and/or
software of the UE 26. For instance, the relationships between the
parameters in the configuration groups and the corresponding CID
parameters may be statically defined by a specification (e.g., the LTE
specification) and therefore stored by or hard-coded in the UE 26.

[0118] Next, the UE 26 obtains CID values for the CID parameters of the
configuration groups (step 104). In one embodiment, the CID values are
unicast from the network to the UE 26. As an example, the CID values may
be unicast from the macro node 22 to the UE 26. In another embodiment,
the CID values are broadcast or multicast to a number of UEs including
the UE 26. For example, in LTE, a new reconfiguration Radio Network
Temporary Identifier (RNTI) may be defined where multiple UEs including
the UE 26 shared the same reconfiguration RNTI. Upon detecting the
reconfiguration RNTI on a PDCCH, the UE 26 changes the CID value for the
CID parameter of the corresponding configuration group accordingly.

[0119] In one particular embodiment, initially, the CID values for the CID
parameters for some or all of the configuration groups may be set to a
physical-layer cell ID of the cell 28 as a default. The heterogeneous
cellular network 20 may then signal new CID values for the CID parameters
to the UE 26 via unicast or broadcast/multicast signaling as needed. This
signaling may be from, for example, the macro node 22. Thus, in the
embodiment where the configuration groups include a downlink
configuration group and an uplink configuration group (e.g., the downlink
and uplink configuration groups 34 and 36), the downlink and uplink
configuration groups may both be configured based on CID values set equal
to or otherwise derived from the physical-layer cell ID of the cell 28
unless other CID values are explicitly signaled by the heterogeneous
cellular communication network 20 (e.g., signaled via RRC signaling).

[0120] When the UE 26 receives the CID values via signaling from the
heterogeneous cellular communication network 20, the actual CID values or
some indicator for the CID values may be received via the signaling. For
example, in one embodiment, the heterogeneous cellular communication
network 20 may signal multiple sets of CID values to the UE 26. Using
FIG. 10 as an example, the heterogeneous cellular communication network
20 may signal a first set of CID values for the pico region 30, a second
set of CID values for the boundary region 32, and a third set of CID
values for at least a portion of the cell 28 that is outside of the pico
region 30 and the boundary region 32. Thereafter, the heterogeneous
cellular communication network 20 may rapidly change the CID values for
the UE 26 by signaling an indicator that corresponds to the desired set
of CID values. This indicator may be, for example, one or a few bits in
the PDCCH, a Media Access Control (MAC) element, or a reserved codepoint
(bit combination) of the control signaling on the PDCCH. One of the sets
of CID values (e.g., the third set of CID values for the cell 28) may be
used as an initial or default set of CID values. Then, as the UE 26 moves
within the cell 28, the macro node 22 may rapidly change the CID values
from one set of CID values to another set of CID values by signaling the
appropriate indicator to the UE 26 via unicast or broadcast/multicast
signaling.

[0121] Once the CID values are obtained, the UE 26 configures the
parameters mapped to the configuration groups based on the corresponding
CID values (step 106). More specifically, for each parameter, a value for
the parameter is derived based on the CID value for the CID parameter of
the corresponding configuration group and the relationship between the
parameter and the CID parameter of the corresponding configuration group.
Note that while FIG. 12 illustrates obtaining all of the CID values and
then configuring all of the parameters in the configuration groups as
sequential steps for clarity and ease of discussion, one of ordinary
skill in the art will immediately recognize that the CID values and the
configuration of the parameters in the corresponding configuration groups
may be performed on a per configuration group basis. Thus, the UE 26 may
obtain one CID value or multiple CID values and then configure the
parameters in the corresponding configuration group(s).

[0122] FIG. 13 illustrates the operation of the heterogeneous cellular
communication network 20 of FIG. 10 to implement the process of FIG. 12
according to one embodiment of the present disclosure. As discussed
above, optionally, in some embodiments, the macro node 22 sends a mapping
of parameters to configuration groups to the UE 26 (step 200). If so, the
UE 26 stores the mapping (step 202). In addition, optionally in some
embodiments, the macro node 22 sends relationships between the parameters
in the configuration groups and the corresponding CID parameters to the
UE 26 (step 204). If so, the UE 26 stores the relationships (step 206).
Note that while the macro node 22 sends the mapping of parameters to
configuration groups and the relationships between the parameters in the
configuration groups to the corresponding CID parameters to the UE 26,
the mapping and/or relationships may alternatively be sent to the UE 26
from another network node.

[0123] Next, the macro node 22, or some other network node, determines or
otherwise obtains a location of the UE 26 within the cell 28 (step 208).
As used herein, "location" is a general term and is not limited to any
absolute geographic location. As such, while the location of the UE 26
may be an absolute location (e.g., latitude and longitude coordinates),
the location of the UE 26 is not limited thereto. The location of the UE
26 may generally be any information that indicates that the UE 26 is
located in the pico region 30, the boundary region 32, or a portion of
the cell 28 that is outside of the pico region 30 and the boundary region
32. For example, the location of the UE 26 may be represented by radio
conditions using various measurements (e.g., pathloss to various network
nodes).

[0124] The macro node 22 then determines a set of CID values for the UE 26
based on the location of the UE 26 within the cell 28 (step 210). For
example, the macro node 22 may store a first set of CID values for the
pico region 30, a second set of CID values for the boundary region 32,
and a third set of CID values for at least a portion of the cell 28 that
is outside of the pico region 30 and the boundary region 32. Then, based
on the location of the UE 26, the macro node 22 selects the appropriate
set of CID values for the UE 26. The macro node 22 then provides the
appropriate set of CID values to the UE 26 (step 212). More specifically,
the macro node 22 may signal the actual CID values in the appropriate set
of CID values to the UE 26. The UE 26 then configures the parameters
mapped to the configuration groups based on the corresponding CID values
(step 214). Again, while the macro node 22 determines the set of CID
values for the UE 26 and provides the set of CID values to the UE 26, the
present disclosure is not limited thereto. The set of CID values for the
UE 26 may be determined by and sent to the UE 26 from another network
node.

[0125]FIG. 14 illustrates the operation of the heterogeneous cellular
communication network 20 of FIG. 10 to implement the process of FIG. 12
according to another embodiment of the present disclosure. As discussed
above, optionally, in some embodiments, the macro node 22 sends a mapping
of parameters to configuration groups to the UE 26 (step 300). If so, the
UE 26 stores the mapping (step 302). In addition, optionally in some
embodiments, the macro node 22 sends relationships between the parameters
in the configuration groups and the corresponding CID parameters to the
UE 26 (step 304). If so, the UE 26 stores the relationships (step 306).
Note that while the macro node 22 sends the mapping of parameters to
configuration groups and the relationships between the parameters in the
configuration groups to the corresponding CID parameters to the UE 26,
the mapping and/or relationships may alternatively be sent to the UE 26
from another network node.

[0126] Next, the macro node 22 sends two or more sets of CID values to the
UE 26 for the CID parameters of the configuration groups for the UE 26
(step 308). For example, the sets of CID values may include a first set
of CID values for the pico region 30, a second set of CID values for the
boundary region 32, and a third set of CID values for at least a portion
of the cell 28 that is outside of the pico region 30 and the boundary
region 32. Again, it should be noted that the two or more sets to CID
values may be sent to the UE 26 from a network node other than the macro
node 22. The UE 26 stores the sets of CID values (step 310).

[0127] The macro node 22 then determines or otherwise obtains a location
of the UE 26 within the cell 28 (step 312). As used herein, "location" is
a general term and is not limited to any absolute geographic location. As
such, while the location of the UE 26 may be an absolute location (e.g.,
latitude and longitude coordinates), the location of the UE 26 is not
limited thereto. The location of the UE 26 may generally be any
information that indicates that the UE 26 is located in the pico region
30, the boundary region 32, or a portion of the cell 28 that is outside
of the pico region 30 and the boundary region 32. For example, the
location of the UE 26 may be represented by radio conditions using
various measurements (e.g., pathloss to various network nodes).

[0128] The macro node 22 then selects an appropriate set of CID values for
the UE 26 based on the location of the UE 26 within the cell 28 (step
314). For example, if the UE 26 is located within the boundary region 32,
the macro node 22 selects the set of CID values for the boundary region
32. The macro node 22 then provides an indicator of the appropriate set
of CID values to the UE 26 (step 316). More specifically, the macro node
22 may signal the indicator of the appropriate set of CID values, rather
than the actual CID values, to the UE 26. The UE 26 then configures the
parameters mapped to the configuration groups based on the corresponding
set of CID values (step 318). Note that while the macro node 22 selects
the appropriate sent of CID values for the UE 26 and provides the
indicator of the appropriate set of CID values to the UE 26 in this
embodiment, the present disclosure is not limited thereto. The
appropriate set of CID values selected by and the indicator of the
appropriate CID values sent by another network node.

[0129]FIG. 15 illustrates the operation of the heterogeneous cellular
communication network 20 of FIG. 10 to implement the process of FIG. 12
according to another embodiment of the present disclosure. As discussed
above, optionally, in some embodiments, the macro node 22 sends a mapping
of parameters to configuration groups to the UE 26 (step 400). If so, the
UE 26 stores the mapping (step 402). In addition, optionally in some
embodiments, the macro node 22 sends relationships between the parameters
in the configuration groups and the corresponding CID parameters to the
UE 26 (step 404). If so, the UE 26 stores the relationships (step 406).
Note that while the macro node 22 sends the mapping of parameters to
configuration groups and the relationships between the parameters in the
configuration groups to the corresponding CID parameters to the UE 26,
the mapping and/or relationships may alternatively be sent to the UE 26
from another network node.

[0130] Next, the macro node 22 sends two or more sets of CID values to the
UE 26 for the CID parameters of the configuration groups for the UE 26
(step 408). For example, the sets of CID values may include a first set
of CID values for the pico region 30, a second set of CID values for the
boundary region 32, and a third set of CID values for at least a portion
of the cell 28 that is outside of the pico region 30 and the boundary
region 32. Again, it should be noted that the two or more sets to CID
values may be sent to the UE 26 from a network node other than the macro
node 22. The UE 26 stores the sets of CID values (step 310).

[0131] In this embodiment, the UE 26 then determines or otherwise obtains
a location of the UE 26 within the cell 28 (step 412). As used herein,
"location" is a general term and is not limited to any absolute
geographic location. As such, while the location of the UE 26 may be an
absolute location (e.g., latitude and longitude coordinates), the
location of the UE 26 is not limited thereto. The location of the UE 26
may generally be any information that indicates that the UE 26 is located
in the pico region 30, the boundary region 32, or a portion of the cell
28 that is outside of the pico region 30 and the boundary region 32. For
example, the location of the UE 26 may be represented by radio conditions
using various measurements (e.g., pathloss to various network nodes). The
UE 26 then selects an appropriate set of CID values for the UE 26 based
on the location of the UE 26 within the cell 28 (step 414). For example,
if the UE 26 is located within the boundary region 32, the UE 26 selects
the set of CID values for the boundary region 32. The UE 26 notifies the
macro node 22 of the selected set of CID values (step 416). The UE 26
then configures the parameters mapped to the configuration groups based
on the corresponding set of CID values (step 418).

[0132]FIG. 16 illustrates one example of configuration groups and the
change in the CID values for the CID parameters of the configuration
groups according to one embodiment of the present disclosure. As
illustrated, three configuration groups are defined for the UE 26,
namely, a CSI-RS configuration group, a downlink transmission
configuration group, and an uplink transmission configuration group. The
CSI-RS configuration group includes parameters such as, for example,
parameters that define which resource elements to measure upon, sequences
to use, and the like. The downlink transmission configuration group
includes parameters such as, for example, a downlink scrambling
parameter, a CRS location parameter, and the like. The uplink
transmission configuration group includes parameters such as, for
example, an uplink scrambling parameter, a DM-RS structure parameter, and
the like.

[0133] As illustrated, at time 0, the UE 26 is located in the cell 28
outside of the pico region 30 and the boundary region 32. As such, the
set of CID values for the UE 26 is 0, 0, 0 (i.e., the CID values for all
three configuration groups are CID values associated with the macro node
22). At time 1, the UE 26 has moved into the boundary region 32. As such,
the set of CID values for the UE 26 is 0, 0, 1 (i.e., the CID values for
the CSI-RS configuration group and the downlink transmission
configuration group are CID values associated with the macro node 22, and
the CID value for the uplink transmission configuration group is a CID
value associated with the pico node 24). In this manner, the CID value
for the uplink transmission configuration group ensures uplink
orthogonality at the pico node 24 with other UEs connected to the pico
node 24, and the CID values for the CSI-RS and downlink transmission
configuration groups remain as CID values associated with the macro node
22 as the UE 26 still receives downlink transmissions from the macro node
22. Lastly, at time 2, the UE 26 has moved into the pico region 30. As
such, the set of CID values for the UE 26 is set to 1, 1, 1 (i.e., the
CID values for all three configuration groups are CID values associated
with the pico node 24). In this manner, the CID values for all three
configuration groups are CID values associated with the pico node 24
since both the downlink and uplink transmissions are handled by the pico
node 24.

[0134]FIG. 17 is a block diagram of the macro node 22 according to one
embodiment of the present disclosure. As illustrated, the macro node 22
includes one or more transceiver subsystems 38 and a processing subsystem
40. One of the one or more transceiver subsystems 38 generally includes
analog and, in some embodiments, digital components for sending and
receiving data to and from UEs within the cell 28. In addition, the one
or more transceiver subsystems 38 may include one or more additional
transceiver subsystems 38 for sending data to or receiving data from
other macro nodes and/or sending data to and receiving data from other
network nodes. In particular embodiments, each of the one or more
transceiver subsystems 38 may represent or include radio-frequency (RF)
transceivers, or separate RF transmitters and receivers, capable of
transmitting suitable information wirelessly to other network components
or nodes. From a wireless communications protocol view, the one or more
transceiver subsystems 38 implement at least part of Layer 1 (i.e., the
Physical or "PHY" Layer).

[0135] The processing subsystem 40 generally implements any remaining
portion of Layer 1 as well as functions for higher layers in the wireless
communications protocol (e.g., Layer 2 (data link layer), Layer 3
(network layer), etc.). In particular embodiments, the processing
subsystem 40 may comprise, for example, one or several general-purpose or
special-purpose microprocessors or other microcontrollers programmed with
suitable software and/or firmware to carry out some or all of the
functionality of the macro node 22 described herein. In addition or
alternatively, the processing subsystem 40 may comprise various digital
hardware blocks (e.g., one or more Application Specific Integrated
Circuits (ASICs), one or more off-the-shelf digital and analog hardware
components, or a combination thereof) configured to carry out some or all
of the functionality of the macro node described herein. Additionally, in
particular embodiments, the above described functionality of macro node
22 may be implemented, in whole or in part, by processing subsystem 40
executing software or other instructions stored on a non-transitory
computer-readable medium, such as random access memory (RAM), read only
memory (ROM), a magnetic storage device, an optical storage device, or
any other suitable type of data storage components. Of course, the
detailed operation for each of the functional protocol layers, and thus
the one or more transceiver subsystems 38 and the processing subsystem
40, will vary depending on both the particular implementation as well as
the standard or standards supported by the macro node 22.

[0136]FIG. 18 is a block diagram of the pico node 24 according to one
embodiment of the present disclosure. As illustrated, the pico node 24
includes one or more transceiver subsystems 42 and a processing subsystem
44. One of the one or more transceiver subsystems 42 generally includes
analog and, in some embodiments, digital components for sending and
receiving data to and from UEs within the pico region 30. In addition,
the one or more transceiver subsystems 42 may include one or more
additional transceiver subsystems 42 for sending data to or receiving
data from the macro node 22 and/or sending data to and receiving data
from other network nodes. In particular embodiments, each of the one or
more transceiver subsystems 42 may represent or include radio-frequency
(RF) transceivers, or separate RF transmitters and receivers, capable of
transmitting suitable information wirelessly to other network components
or nodes. From a wireless communications protocol view, the one or more
transceiver subsystems 42 implement at least part of Layer 1 (i.e., the
Physical or "PHY" Layer).

[0137] The processing subsystem 44 generally implements any remaining
portion of Layer 1 as well as functions for higher layers in the wireless
communications protocol (e.g., Layer 2 (data link layer), Layer 3
(network layer), etc.). In particular embodiments, the processing
subsystem 44 may comprise, for example, one or several general-purpose or
special-purpose microprocessors or other microcontrollers programmed with
suitable software and/or firmware to carry out some or all of the
functionality of the pico node 24 described herein. In addition or
alternatively, the processing subsystem 44 may comprise various digital
hardware blocks (e.g., one or more Application Specific Integrated
Circuits (ASICs), one or more off-the-shelf digital and analog hardware
components, or a combination thereof) configured to carry out some or all
of the functionality of the macro node described herein. Additionally, in
particular embodiments, the above described functionality of pico node 24
may be implemented, in whole or in part, by processing subsystem 44
executing software or other instructions stored on a non-transitory
computer-readable medium, such as random access memory (RAM), read only
memory (ROM), a magnetic storage device, an optical storage device, or
any other suitable type of data storage components. Of course, the
detailed operation for each of the functional protocol layers, and thus
the one or more transceiver subsystems 42 and the processing subsystem
44, will vary depending on both the particular implementation as well as
the standard or standards supported by the pico node 24.

[0138]FIG. 19 is a block diagram of the UE 26 according to one embodiment
of the present disclosure. As illustrated, the UE 26 includes a
transceiver subsystem 46 and a processing subsystem 48. The transceiver
subsystem 46 generally includes analog and, in some embodiments, digital
components for sending and receiving data to and from the macro node 22
and the pico node 24. In particular embodiments, each of the one or more
transceiver subsystems 46 may represent or include radio-frequency (RF)
transceivers, or separate RF transmitters and receivers, capable of
transmitting suitable information wirelessly to other network components
or nodes. From a wireless communications protocol view, the transceiver
subsystem 46 implements at least part of Layer 1 (i.e., the Physical or
"PHY" Layer).

[0139] The processing subsystem 48 generally implements any remaining
portion of Layer 1 as well as functions for higher layers in the wireless
communications protocol (e.g., Layer 2 (data link layer), Layer 3
(network layer), etc.). In particular embodiments, the processing
subsystem 48 may comprise, for example, one or several general-purpose or
special-purpose microprocessors or other microcontrollers programmed with
suitable software and/or firmware to carry out some or all of the
functionality of the UE 26 described herein. In addition or
alternatively, the processing subsystem 48 may comprise various digital
hardware blocks (e.g., one or more Application Specific Integrated
Circuits (ASICs), one or more off-the-shelf digital and analog hardware
components, or a combination thereof) configured to carry out some or all
of the functionality of the macro node described herein. Additionally, in
particular embodiments, the above described functionality of UE 26 may be
implemented, in whole or in part, by processing subsystem 48 executing
software or other instructions stored on a non-transitory
computer-readable medium, such as random access memory (RAM), read only
memory (ROM), a magnetic storage device, an optical storage device, or
any other suitable type of data storage components. Of course, the
detailed operation for each of the functional protocol layers, and thus
the transceiver subsystem 46 and the processing subsystem 48, will vary
depending on both the particular implementation as well as the standard
or standards supported by the UE 26.

[0140] While this disclosure is in the framework of LTE, a person skilled
in the art will immediately recognize that the principles can be applied
to other standards as well. Further, the concepts described herein
provide a number of advantages. For example, the concepts described
herein make it possible to decouple the configuration of various
parameters, or functionality, of the UE from the system information while
maintaining low signaling overhead for configuration messages. Such
decoupling provides flexibility needed in non-traditional deployment
types such as heterogeneous deployments or distributed antenna systems
where it may be beneficial to transmit the system information in a
different manner than unicast data and CSI-RS. Also, dividing parameters,
or functionality, into different configuration groups where the
configuration of the parameters in each configuration group is at least
partially based on a corresponding CID value provides further decoupling
opportunities. Decoupling of configuration for downlink and uplink is a
primary example particularly useful in a heterogeneous deployment where
the service area of a node might need to be different in downlink and
uplink.

[0141] The following acronyms are used throughout this disclosure.

[0142] ARQ Automatic Repeat Request

[0143] ASIC Application Specific Integrated Circuit

[0144] BCCH Broadcast Control Channel

[0145] BCH Broadcast Channel

[0146] CCCH Common Control Channel

[0147] CDMA Code Division Multiple Access

[0148] CDMA2000 A family of mobile technology standards which use CDMA
channel access to send voice, data, and signaling between mobile phones
and cell sites

[0149] CID Configuration Identity

[0150] CRS Cell-Specific Reference Signal

[0151] CSI Channel-State Information

[0152] CSI-RS CSI Reference Signal

[0153] DCCH Dedicated Control Channel

[0154] DCI Downlink Control Information

[0155] DFT Discrete Fourier Transform

[0156] DL-SCH Downlink Shared Channel

[0157] DM-RS Demodulation Reference Signal

[0158] DTCH Dedicated Traffic Channel

[0159] FDD Frequency Division Duplexing

[0160] HSPA High Speed Packet Access

[0161] ID Identity

[0162] LTE Long Term Evolution

[0163] m2 Squared Meters

[0164] MAC Media Access Control

[0165] Mbit/s Megabits Per Second

[0166] MBMS Multicast Broadcast Multimedia Services

[0167] MBSFN Multimedia Broadcast Over A Single Frequency

[0168] Network

[0169] MCCH Multicast Control Channel

[0170] MCH Multicast Channel

[0171] ms Milliseconds

[0172] MTCH Multicast Traffic Channel

[0173] OFDM Orthogonal Frequency Division Multiplexing

[0174] PBCH Physical Broadcast Channel

[0175] PCCH Paging Control Channel

[0176] PCFICH Physical Control Format Indicator Channel

[0177] PCH Paging Channel

[0178] PDCCH Physical Downlink Control Channel

[0179] PDSCH Physical Downlink Shared Channel

[0180] PHICH Physical Hybrid-ARQ Indicator Channel

[0181] PMCH Physical Multicast Channel

[0182] PRACH Physical Random Access Channel

[0183] PRS Positioning Reference Signal

[0184] PSS Primary Synchronization Signal

[0185] PUCCH Physical Uplink Control Channel

[0186] PUSCH Physical Uplink Shared Channel

[0187] RACH Random Access Channel

[0188] RNTI Radio Network Temporary Identifier

[0189] RRC Radio Resource Control

[0190] RRU Remote Radio Unit

[0191] RS Reference Signal

[0192] SIR Signal-to-Interference

[0193] SRS Sounding Reference Signal

[0194] SSS Secondary Synchronization Signal

[0195] TDD Time Division Duplexing

[0196] TTI Transmission Time Interval

[0197] UCI Uplink Control Information

[0198] UE User Equipment Device

[0199] UL-SCH Uplink Shared Channel

[0200] WCDMA Wideband Code Division Multiple Access

[0201] Those skilled in the art will recognize improvements and
modifications to the preferred embodiments of the present disclosure. All
such improvements and modifications are considered within the scope of
the concepts disclosed herein and the claims that follow.